Type bar action for typewriting machines



June 13, 1950 c. T. RICE 2,511,008

TYPE BAR ACTION FOR TYPEWRITING MACHINES Filed July 27, 1946 s Sheets-Sheet 1 Z7 4 ATTORNEY June 13, 1950 I c. T. RICE ,00

TYPE BAR ACTION FOR TYPEWRITING MACHINES Filed July '37, 1946 5 Sheets-Sheet 2 INVENT R ATTORNEY June 13, 1950 c. T. RICE 2,511,008

TYPE BAR ACTION FOR TYPEWRITING MACHINES Filed July 27, 1946 3 Sheets-Sheet 5 INVENT R M /Z;VATTORNEY Patented June 13, 1950 a I UNITED STATES PATENT OFFICE TYPE BAR ACTION FOR TYPEWRITING MACHINES Claude T. Rice, Brooklyn, N. Y.

Application July 27, 1946, Serial No. 686,620

1 17 Claims.

This invention relates to writing machine or typewriter actions in general, and more especially to silent or noiseless typewriter actions.

Among the objects of the present invention, it is aimed to provide an improved silent typewriter action including an actuatin key, a type bar and a connecting mechanism which effect a variable motion including an accelerated initial motion, a decelerated second motion after the type head of the type bar selected has been brought into printing position, and then a third motion resulting from the momentum generated by the initial motion characterized by a pressure blow as distinguished from a striking blow.

More specifically, the present invention aims to provide an improved typewriter action using a toggle linkage to generate an initial accelerated motion, a second d'ecelerated motion when the toggle linkage approaches dead center, and a third motion characterized by a pressure blow as distinguished from a striking blow when the toggle linkage moves to and beyond dead center.

It is still another object of the present invention to provide an improved typewriter action using a toggle linkage cooperating with a control for connecting the toggle linkage to the type bar to generate an initial accelerated motion, a second decelerated motion when the toggle linkage approaches dead center; and a third motion characterized by a pressure blow as distinguished from a strikin blow when the toggle linkage moves to and beyond dead center.

These and other features, capabilities and advantages of the present invention will appear from the subjoined detail description of specific embodiments thereof illustrated in the accompanying drawings, in which Figs. 1 and 2 illustrate successive positions in side elevation of one embodiment.

Figs. 3 and 4 illustrate successive positions in side elevation of a second embodiment.

Figs. 5 and 6 illustrate successive positions in side elevation of third embodiment; and

Figs. 7 and 8 illustrate successive positions in side elevation of a fourth embodiment.

In the embodiment illustrated in Figs. 1 and 2, the platen i is illustrative of the class of platens in which the platen is shifted to receive the upper case characters, being illustrated in its descended, normal position, to receive lower case characters. The type bar 2' is pivotally mounted on the fixed pivot pin or shaft 3, being provided with a type head having a lower case character 4 and an upper case character 5. The key bar 6', illustrative of the conventional key bar, is pivotally mounted at one end on the fixed pivot pin or shaft 1, and at its other end provided with a conventional In the interest of an understanding of the operation of this embodiment and of showing its relation to the three other embodiments hereinafter to be described", it is here noted that in all four embodiments there are only three fixed pivot pins, such as the pivot pins 3 and l aforesaid, and the pivot pin 9 nowto be described. The pivot pin 9 extends through the angle or bend in the bell crank lever or bent lever It, which has a short broad arm [I and a long arm l 2. The arm I i has pivotally connected thereto the upper end of the link 13 which is pivotally connected at its lower end to the key bar 6. Above the pivotal connection with the link 63, the arm H is connected to the tension spring It for returnin the typewriter action to normal position or position of rest after actuation thereof in accordance with convention.

The long arm l2 forms a toggle linkage with the link IS, the action of which constitutes an important, if not the main, feature of the present invention. The link i5 is pivotally connected at one end to the free end of the arm 12, and at its other end is pivotally connected to the short link l6 constituting apart of the control for the type bar 2'. The link 15 is fulcrumed or pivoted intermediate its ends to the upper end of the link ll constituting another part of the control for the type bar 2, the lower end of which link H is pivotally connected to the free end of the short arm or extension 18 integral with the type bar 2.

The link l5 functionally is divided into two arms I9 and 20, the arm l9 cooperating with the arm l'2 to form a toggle linkage, the movement of which from the full line position shown in Fig. 1 toward the dotted line position shown in Fig. 1, upon actuation effecting an accelerated, rapid initial motion, the movement of which when approaching and passing the dead center, dotted line position shown in Fig. 1, being decelerated, and the motion of which from the dotted line position of Fig. I to the full line position shown in Fig. 2, being characterized by a pressure blow as distinguished from a striking blow to effect a silent or noiseless printing impression by the type bar 2.

To aid in effecting a uniform pressure blow by a plurality of actions, and in properly position ing the type bar 2' preparatory to an actuation, preferably there is provided a stop 2i which, in the present instance, is positioned to engage the rear face of the; type head of the type bar 2, as shown in the full line position in Fig". 1.

Furthermore, to limit the arm I2 in the final printing position of the type bar 2 and thereby prevent any repeat printing action by the type bar 2, preferably a second stop 22 is provided, in the present instancepositioned to engage the upper edge of the arm l2 in the printin position of the type bar 2.

The. embodiment shown in Figs. 3 and 4 differs; primarily from the embodiment shown inv Figs. 1 and 2 in that the link I6 is omitted, and in place thereof, the type bar 23 is provided with a cam slot 24 having an upper lobe 25 and a lower lobe 2E. The type bar 23, in the present instance, is also shown as slightly curved as compared to the type bar 2, the arm 21 forming a sharper angle with the main part of the type bar 23, than is the angle formed between the arm l8 and the main part of the type bar 2, and the link 28 is slightly shorter than the link H. Furthermore, the are described by the arm 29 from dead center to printing position of the type bar 23 in the present instance approximates 10, as compared to approximately 7 described by the arm I2 from dead center to printing position of the type bar 2. The arcs described by the arms l2 and 29, as well as the comparative lengths of the arms and links of these two embodiments may, of course, vary without departing from the general spirit of the invention.

In the embodiment illustrated in Figs. 3 and 4, in retracted position, the pin 30 at the free end of the link 3| will be positioned in the lobe 25 of the cam slot 24, in dead center position it will be positioned approximately at the conjunction of the lobes 25 and 26, and in printing position the pin 30 will be positioned in the lobe 26.

The fact remains, however, that the toggle action of the arm 29 and link 3| will cooperate with the control for the type bar 2 characterized by the link 28 and cam slot 24 in substantially the same way as the toggle action of the arm !2 and link E of the embodiment illustrated in Figs. 1 and 2 will cooperate with the control for the type bar 2 characterized by the links H and I6.

The embodiment illustrated in Figs. 5 and 6 is distinguished from the embodiment illustrated in Figs. 3 and 4 primarily in that the arm 28 of the embodiment illustrated in Figs. 3 and 4 is eliminated, and in place thereof the arm 32 is formed integral with the type bar 33, and the arm 32 or the type bar 33 in the area between the cam slot 34 and the enlargement 35 surrounding its fixed pivot pin 36, or both, is yieldable, being preferabl composed of some flexible metal, so that when the arm 3'1 moves from the dead center position in Fig. 5 to the printing position of the type bar 33, this yieldability will permit the pin 38 of the link 39 to move from the conjunction between the lobes 40 and 4| of the cam slot 34 into the lobe 4|.

It should also be noted that due to the fewer moving parts in the embodiments of Figs. 3 and. 4 on the one hand, and Figs. 5 and 6 on the other hand, as compared to the embodiment illustrated in Figs. 1 and 2, the limiting stop, such as the limiting stop 2|, may be dispensed with.

The embodiment illustrated in Figs. '7 and 8 is substantially identical to the embodiment illustrated in Figs. 1 and 2 except that the key bar 42 of this last embodiment is connected to the type bar 43 instead of being connected to the bell crank lever 44; see for comparison, the link 13 of the embodiment illustrated in Figs. 1 and 2.

In this last embodiment, the arm 45 of the type bar 43 is provided with an extension 46 beyond the pivotal connection of the arm 45 with the link 41, which extension 46 is in turn connected to the upper end of the arm 48 of the bell crank lever 49 by the link 50, the lower arm 5| of which bell crank lever 49 is connected to the key bar 42 by the link 52.

The embodiment illustrated in Figs. '7 and 8 is submitted primarily to illustrate the flexibility of this typewriter action with respect to its con-- nection to a key bar to fit in with various con-- ventional typewriter constructions on the market today.

It is obvious that various changes and modifications may be made to the details of construction without departing from the general spirit of the invention as set forth in the appended claims.

I claim:

1. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, an arm pivotally mounted on a fixed pivot, a link pivotally connected at one end to one end of said arm, a control including a first means and a second means, said first means extending from said extension to said link and pivotally connected to said link intermediate its ends, said second means operatively associating the other end of said link with said type bar adjacent its head to vary the distance between said head and said other end of said link as the head is moved into and out of printing relation to said platen, a spring operatively connected to said linkage normally to maintain it and return it to position of rest, and means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said arm and link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

2. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a link pivotally connected at one end to one end of said lever, a control including a first means and a second means, said first means extending from said extension to said link and pivotally connected to said link intermediate its ends, said second means operatively associating the other end of said link with said type bar adjacent its head to vary the distance between said head and said other end of said link as the head is moved into and out of printing relation to said platen, and means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen in opposition to said spring when said key bar is actuated, said lever and link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

3. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining: said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end: to the end of the other arm of said lever, a control including a first means and a second means, said first means extending from said. extension to said first link and pivotally connected to said first link intermediate its ends, said second means operatively associating the other end of said first link with said type bar adjacent its head, and a second linkv pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever toactuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated inopposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

4. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type oar having an extension beyond its fixed pivot, a: lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including a first means and a second means, said first means comprising a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said second means operatively associating the other end of said first link with said type bar adjacent its head, and a third link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkageand therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motioncharacterized by a pressure thrust when passing dead center.

5. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, alinkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar= having an extension beyond its fixed pivot, alever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected atone end to one end of said lever, a control including a first means and a second means, said first means comprising a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said second means operatively associating the other end of said first link with said type bar adjacent its head, and means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar intoprinting relation with said platen in opposition to said spring when said key bar is actuated, said lever and first link forming a toggle actionand when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a deeelerated motion characterized by a pressure thrust when passing dead center.

6*. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a first linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected toone arm of said lever for normally maintaining said first linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to one end of said lever, a control including a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said control also including a third link pivotally connected at one end to the other end of said first link and at its other end pivotally connected to said type bar adjacent its head, and means for operatively connecting said first linkage to said key bar to actuate said first linkage and therewith said type bar into printing relation with said platen in opposition to said spring when said key bar is actuated, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

7. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said control also including a third link pivotally connected at one end to the other end of said first link and at its other end pivotally connected to said type bar adjacent its head, and a third link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated inopposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

8. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, type bar having an extension beyond its fixed pivot, a lever fulcrunied on a fixed pivot, a spring connected to one oi said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including an auxiliary bar integral with and extending from said extension to said first link and pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, a pin at the free end of said first link riding in said slot, and said type bar being yieldable in part to enable the head of said type bar to be deflected from said auxiliary bar when in printing relation to said platen, and a second link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

9. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, and a pin at the free end of said first link riding in said slot, and a third link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

10. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to one end of said lever, a control including a first means and a second means, said first means comprising a second link pivotally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said second means operatively associating the other end of said first link with said type bar adjacent its head, means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen in opposition to said spring when said key bar is actuated, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center, a first stop determining the position of said type bar in position of rest, and a second stop for arresting said lever when said type bar is in printing relation with said platen.

11. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a link pivotally connected at one end to one end of said lever, a control including a first means and a second means, said first means extending from said extension to said link and pivotally connected to said link intermediate its ends, said second means operatively associating the other end of said link with said type bar adjacent its head to vary the distance between said head and said other end of said link as the head is moved into and out of printing relation to said platen, means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen in opposition to said spring when said key bar is actuated, said lever and link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center, and a stop for arresting said lever when said type bar is in printing relation with said platen.

12. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, said type bar having an extension beyond its fixed pivot, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including an auxiliary bar integral with and extending from said extension to said first link and pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, a pin at the free end of said first link riding in said slot, and said type bar being yieldable in part to enable the head of said type bar to be deflected from said auxiliary bar when in printing relation to said platen, a second link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said first linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereone arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including a second link pivot ally connected at one end to one end of said extension and at its other end pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, and a pin at the free end of said first link riding in said slot, a third link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen whensaid key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center, and a stop for arresting said lever when said type bar is in printing relation with said platen,

14. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage ineluding a type bar pivotally mounted on a fixed pivot and having a head thereon, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including an auxiliary bar integral with said type bar and extending from its fixed pivot to said first link and pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, a pin at the free end of said first link riding in said slot, and said auxiliary bar and type bar being yieldable in part to enable the head of said type bar to be deflected relative to said auxiliary bar when in printing relation to said platen, and a second link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

15. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, a lever fulcrumed on a fixed pivot, a spring connected to one arm of said lever for normally maintaining said linkage in position of rest and for restoring it to position of rest, a first link pivotally connected at one end to the end of the other arm of said lever, a control including an auxiliary bar integral with said type bar and extending from its fixed pivot to said first link and pivotally connected to said first link intermediate its ends, said control also including a cam slot in said type bar adjacent its head, a pin at the free end of said first link riding in said slot, and said auxiliary bar being yieldable to enable the head of said type bar to be deflected relative to said auxiliary bar when in printing relation to said platen, and a second link pivotally connected at one end to said key bar and at its other end pivotally connected to said one arm of said lever to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said lever and first link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

16. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, an arm pivotally mounted on a fixed pivot, a link pivotally connected at one end to one end of said arm, a control including a first means and a second means, said first means extending from said type bar to said link and pivotally connected to said link intermediate its ends, said second means operatively associating the other end of said link with said type bar adjacent its head to vary the distance between said head and said other end of said link as the head is moved into and out of printing relation to said platen, a spring operatively connected to said linkage normally to maintain it and return it to position of rest, and means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said arm and link forming a toggle action and when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust when passing dead center.

'17. The combination with a platen, of a key bar pivotally mounted on a fixed pivot, a linkage including a type bar pivotally mounted on a fixed pivot and having a head thereon, two interconnected toggles having an intermediate common member, one end of said interconnected toggles pivotally connected to said type bar, a control means pivotally connected at one of its ends to said intermediate common member intermediate its ends and at its other end pivotally connected to said type bar, the other end of said interconnected toggles pivotally mounted on a fixed pivot, a spring operatively connected to said linkage normally to maintain it and return it to position of rest, and means for operatively connecting said linkage to said key bar to actuate said linkage and therewith said type bar into printing relation with said platen when said key bar is actuated in opposition to said spring, said interconnected toggles when actuated by said key bar performing an initial accelerated motion before reaching dead center and thereupon performing a decelerated motion characterized by a pressure thrust after passing dead center.

CLAUDE T. RICE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS- Number Name Date 1,767,876 Going June 24, 1930 1,951,453 Stickney Mar. 20, 1934 

